PCI: dra7xx: Reset all BARs during initialization

dra7xx has all base address registers (BAR) enabled by default. Reset all
BARs during initialization and so that BARs are enabled only if they are
actually used.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/dwc/pci-dra7xx.c

@@ -335,10 +335,23 @@ static irqreturn_t dra7xx_pcie_irq_handler(int irq, void *arg)
 	return IRQ_HANDLED;
 }
 
+static void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
+{
+	u32 reg;
+
+	reg = PCI_BASE_ADDRESS_0 + (4 * bar);
+	dw_pcie_writel_dbi2(pci, reg, 0x0);
+	dw_pcie_writel_dbi(pci, reg, 0x0);
+}
+
 static void dra7xx_pcie_ep_init(struct dw_pcie_ep *ep)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
 	struct dra7xx_pcie *dra7xx = to_dra7xx_pcie(pci);
+	enum pci_barno bar;
+
+	for (bar = BAR_0; bar <= BAR_5; bar++)
+		dw_pcie_ep_reset_bar(pci, bar);
 
 	dra7xx_pcie_enable_wrapper_interrupts(dra7xx);
 }